The present invention relates to couplings and clamps, and has particular usefulness in relation to mounting assemblies for sensors and instrumentation.
Heretofore, a wide variety of couplings and mounting clamps have been used to join rigid members at different angles, such as are used in the coupling of cross-bars and supports, scaffolding members, and the like. A number of existing coupling constructions utilize a clamp element that clamps about a main support bar, with a side rail or rails also connected to the clamp. While many clamps provide for the right-angle connection of two members or rails, in some of these prior couplings the clamp is connected to the side rail in a manner which permits the side rail to extend at an oblique angle to the main support. Such an obliquely extending connection would be used in the mounting of a diagonal brace on a scaffolding or the like. Further, in some prior couplings, the side rail is provided with an ear or lobe on one end that extends off from the central axis of the side rail, in order to offset the cross-rail from the clamp body that extends across the clamped member. With two such side rails and adjacent clamps, this offset arrangement permits two side arms to be mounted in diametric opposition on a single main support beam or member.
One drawback of certain prior coupling assemblies has been the provision of a highly adjustable assembly that provides a rigid coupling when assembled, but which does not provide for the mounting of diametrically opposed side rails. For example, in assemblies having a single clamp that extends across the support beam to mount two diametrically opposed side rails, adjustment of one side rail involves the releasing of both side rails. In such an assembly, a single side rail can, therefore, not be adjusted without simultaneous adjustment of the opposing rail. In other assemblies that use a separate clamp element for each side rail, most mounting assemblies do not provide for the diametrically opposed positioning of the side rails. Those assemblies which use offsetting ears or tabs to offset the side rail result in a moment arm or lever being created between the side rail and the clamp element. As a result, when weight is applied to the side rail, not only is there a longitudinal flexing of the side rail, but a rotational torque is created by the moment arm about the clamp element. In assemblies that require close tolerances, or in assemblies in which a vacuum cup is used to lift or position heavy objects with associated large stresses being exerted on the clamp, this additional factor must be accommodated either by adjusting the positioning of the side rail, or by increasing the size, weight, or type of material used in the mounting elements in order to provide a sufficiently rigid mounting assembly.